new file 100644
/*
* Portions Copyright 2008, 2010 VMware, Inc.
*/
#ifndef __ARCH_X86_64_ATOMIC__
#define __ARCH_X86_64_ATOMIC__
#include <asm/alternative.h>
#if defined(__VMKLNX__)
#include "vmkapi.h"
#endif /* defined(__VMKLNX__) */
/* atomic_t should be 32 bit signed type */
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
#ifdef CONFIG_SMP
#define LOCK "lock ; "
#else
#define LOCK ""
#endif
* Make sure gcc doesn't try to be clever and move things around
* on us. We need to use _exactly_ the address the user gave us,
* not some alias that contains the same information.
typedef struct { volatile int counter; } atomic_t;
#define ATOMIC_INIT(i) { (i) }
/**
* atomic_read - read atomic variable
* @v: pointer of type atomic_t
*
* Atomically reads the value of @v.
#define atomic_read(v) ((v)->counter)
* atomic_set - set atomic variable
* @i: required value
* Atomically sets the value of @v to @i.
#define atomic_set(v,i) (((v)->counter) = (i))
* atomic_add - add integer to atomic variable
* @i: integer value to add
* Atomically adds @i to @v.
/* _VMKLNX_CODECHECK_: atomic_add */
static __inline__ void atomic_add(int i, atomic_t *v)
{
vmk_AtomicPrologue();
__asm__ __volatile__(
LOCK_PREFIX "addl %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
vmk_AtomicEpilogue();
}
* atomic_sub - subtract the atomic variable
* @i: integer value to subtract
* Atomically subtracts @i from @v.
/* _VMKLNX_CODECHECK_: atomic_sub */
static __inline__ void atomic_sub(int i, atomic_t *v)
LOCK_PREFIX "subl %1,%0"
* atomic_sub_and_test - subtract value from variable and test result
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
static __inline__ int atomic_sub_and_test(int i, atomic_t *v)
unsigned char c;
LOCK_PREFIX "subl %2,%0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"ir" (i), "m" (v->counter) : "memory");
return c;
* atomic_inc - increment atomic variable
* Atomically increments @v by 1.
/* _VMKLNX_CODECHECK_: atomic_inc */
static __inline__ void atomic_inc(atomic_t *v)
LOCK_PREFIX "incl %0"
:"m" (v->counter));
* atomic_dec - decrement atomic variable
* Atomically decrements @v by 1.
/* _VMKLNX_CODECHECK_: atomic_dec */
static __inline__ void atomic_dec(atomic_t *v)
LOCK_PREFIX "decl %0"
* atomic_dec_and_test - decrement and test
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all other
* cases.
/* _VMKLNX_CODECHECK_: atomic_dec_and_test */
static __inline__ int atomic_dec_and_test(atomic_t *v)
LOCK_PREFIX "decl %0; sete %1"
:"m" (v->counter) : "memory");
return c != 0;
* atomic_inc_and_test - increment and test
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
static __inline__ int atomic_inc_and_test(atomic_t *v)
LOCK_PREFIX "incl %0; sete %1"
* atomic_add_negative - add and test if negative
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
static __inline__ int atomic_add_negative(int i, atomic_t *v)
LOCK_PREFIX "addl %2,%0; sets %1"
* atomic_add_return - add and return
* Atomically adds @i to @v and returns @i + @v
/* _VMKLNX_CODECHECK_: atomic_add_return */
static __inline__ int atomic_add_return(int i, atomic_t *v)
int __i = i;
LOCK_PREFIX "xaddl %0, %1;"
:"=r"(i)
:"m"(v->counter), "0"(i));
return i + __i;
static __inline__ int atomic_sub_return(int i, atomic_t *v)
return atomic_add_return(-i,v);
* atomic_inc_return - increment by 1 and return
* @v: integer value to increment
* Atomically increments @v by 1 returns @v + 1
* SYNOPSIS:
* #define atomic_inc_return(v)
* RETURN VALUE:
* Returns @v + 1
/* _VMKLNX_CODECHECK_: atomic_inc_return */
#define atomic_inc_return(v) (atomic_add_return(1,v))
#define atomic_dec_return(v) (atomic_sub_return(1,v))
/* An 64bit atomic type */
typedef struct { volatile long counter; } atomic64_t;
#define ATOMIC64_INIT(i) { (i) }
* atomic64_read - read atomic64 variable
* @v: pointer of type atomic64_t
* Doesn't imply a read memory barrier.
#define atomic64_read(v) ((v)->counter)
* atomic64_set - set atomic64 variable
* @v: pointer to type atomic64_t
static __inline__ void atomic64_set(atomic64_t *v, long i)
* Ensure that we do a single movq. Without this, the compiler
* may do write with a constant as two movl operations.
"movq %1, %0"
: "+m" (v->counter)
: "r" (i)
);
#else /* !defined(__VMKLNX__) */
#define atomic64_set(v,i) (((v)->counter) = (i))
* atomic64_add - add integer to atomic64 variable
static __inline__ void atomic64_add(long i, atomic64_t *v)
LOCK_PREFIX "addq %1,%0"
* atomic64_sub - subtract the atomic64 variable
static __inline__ void atomic64_sub(long i, atomic64_t *v)
LOCK_PREFIX "subq %1,%0"
* atomic64_sub_and_test - subtract value from variable and test result
static __inline__ int atomic64_sub_and_test(long i, atomic64_t *v)
LOCK_PREFIX "subq %2,%0; sete %1"
* atomic64_inc - increment atomic64 variable
static __inline__ void atomic64_inc(atomic64_t *v)
LOCK_PREFIX "incq %0"
* atomic64_dec - decrement atomic64 variable
static __inline__ void atomic64_dec(atomic64_t *v)
LOCK_PREFIX "decq %0"
* atomic64_dec_and_test - decrement and test
static __inline__ int atomic64_dec_and_test(atomic64_t *v)
LOCK_PREFIX "decq %0; sete %1"
* atomic64_inc_and_test - increment and test
static __inline__ int atomic64_inc_and_test(atomic64_t *v)
LOCK_PREFIX "incq %0; sete %1"
* atomic64_add_negative - add and test if negative
static __inline__ int atomic64_add_negative(long i, atomic64_t *v)
LOCK_PREFIX "addq %2,%0; sets %1"
* atomic64_add_return - add and return
static __inline__ long atomic64_add_return(long i, atomic64_t *v)
long __i = i;
LOCK_PREFIX "xaddq %0, %1;"
static __inline__ long atomic64_sub_return(long i, atomic64_t *v)
return atomic64_add_return(-i,v);
#define atomic64_inc_return(v) (atomic64_add_return(1,v))
#define atomic64_dec_return(v) (atomic64_sub_return(1,v))
#define atomic_cmpxchg(v, old, new) ((int)cmpxchg(&((v)->counter), old, new))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
* atomic_add_unless - add unless the number is a given value
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
* Atomically adds @a to @v, so long as it was not @u.
* Returns non-zero if @v was not @u, and zero otherwise.
#define atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
for (;;) { \
if (unlikely(c == (u))) \
break; \
old = atomic_cmpxchg((v), c, c + (a)); \
if (likely(old == c)) \
c = old; \
} \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/* These are x86-specific, used by some header files */
#define atomic_clear_mask(mask, addr) \
do { \
vmk_AtomicPrologue(); \
__asm__ __volatile__(LOCK_PREFIX "andl %0,%1" \
: : "r" (~(mask)),"m" (*addr) : "memory") ; \
vmk_AtomicEpilogue(); \
} while (0)
#define atomic_set_mask(mask, addr) \
__asm__ __volatile__(LOCK_PREFIX "orl %0,%1" \
: : "r" ((unsigned)mask),"m" (*(addr)) : "memory"); \
: : "r" (~(mask)),"m" (*addr) : "memory")
: : "r" ((unsigned)mask),"m" (*(addr)) : "memory")
/* Atomic operations are already serializing on x86 */
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()
#define smp_mb__before_atomic_inc() barrier()
#define smp_mb__after_atomic_inc() barrier()
#include <asm-generic/atomic.h>